-LRB- CNN -RRB- -- Five people suffered minor injuries Friday when a duck boat crashed into several other vehicles in downtown Boston , Massachusetts .

The chain-reaction crash happened shortly after noon on a ramp from Embankment Road West to Charles Street Circle , Massachusetts State Police Trooper Thomas Murphy said . At least seven vehicles were involved .

No one was seriously hurt .

Cindy Brown , general manager of Boston Duck Tours , said a piece of fallen equipment caused the crash .

`` A computer box fell off and become lodged under the brake '' pedal , Brown said .

Once the driver dislodged the box , Brown said , the duck boat was able to brake normally .

Brown estimated that the duck boat was traveling between 15 and 20 mph when it crashed .

`` We 're re-inspecting the vehicles that are of the same configuration , '' Brown said .

Duck boats are amphibious vehicles often used for tours on land or water .

Two people were killed this month when a barge hit a duck boat on the Delaware River in Philadelphia , Pennsylvania .

CNN 's Bradley Gallo contributed to this report .

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NEW : A manager says a piece of equipment fell and got stuck under the boat 's brake pedal

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Duck boats are used for tours on land or water

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Two people were killed in a duck boat crash this month in Philadelphia , Pennsylvania